Removed Grouping.isOrdered()
Removed Grouping.isOrdered()

The private postAggregationCalculations function in Grouping was passing
self.orderingFunction to self.extractData, but only if
Grouping.isOrdered returned true. However, the base
DataProvider.extractData function would still order the data using the
self.orderingFunction, rendering Grouping.isOrdered useless.

ScottLogic/insight